Made available in DSpace on 2014-06-12T15:06:56Z (GMT). No. of bitstreams: 2 arquivo1314_1.pdf: 1076602 bytes, checksum: a18fd6306ecc6eaabe27970d785f3373 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / A hipótese de eficiência de mercado (HEM) e as finanças comportamentais são alguns dos mais polêmicos temas no contexto da pesquisa em finanças. Investigações sobre a existência de possíveis vieses comportamentais e se os preços dos ativos efetivamente refletem as informações do momento estão fortemente presentes na atual agenda de pesquisa financeira. Foi objetivo deste trabalho testar a hipótese de que o mercado acionário brasileiro, de 1994 a 2005, mostrou-se eficiente nas formas fraca e semiforte, testando-se também a existência de possíveis movimentos comportamentais - sobre-reações (overreaction) ou reações atrasadas (underreaction). Para tanto, foram utilizadas duas principais linhas metodológicas: (1) comparação entre carteiras que, no passado, foram consideradas perdedoras contra as, neste mesmo período, tidas como vencedoras , baseando-se em testes paramétricos utilizados por De Bondt e Thaler (1985, 1987), Chopra, Lakonishok e Ritter (1992) e Jegadeesh e Titman (1993, 2001), além de outros não-paramétricos; e (2) estudos de eventos, para a observação do comportamento do mercado (índice Ibovespa) nos dias imediatamente anteriores e seguintes a divulgações de notícias macroeconômicas de relevância (PIB, IPCA e taxa Selic), por meio de regressões EGARCH. Entre os resultados empíricos, não foram observadas evidências significantes de overreaction ou underreaction, não tendo a HEM sido rejeitada. Entretanto, na revisão da literatura realizada, foi percebido que o tema ainda carece de maior sistematização e aprofundamento em relação aos seus pressupostos, o que dificulta e traz confusão aos resultados empíricos de diversas pesquisas. Assim, a presente dissertação propôs uma perspectiva alternativa de análise Eficiência Comportamental de Mercado -, sendo um esforço para melhor categorizar as hipóteses de investigação

>Magister Scientiae - MSc / This research undertakes to investigate both long-term and short-term investor overreaction on the JSE Limited (JSE) over the period from 1 January 2002 to 31 December 2009. The period covers the restructuring and reform of the JSE in the early 2000s to the end of global financial market crisis in late 2008/2009, which can be regarded as a complete economic cycle. The performances of the winner and loser portfolios are evaluated by assessing their cumulative abnormal returns (CAR) over a 24-month holding period. The test results show no evidence of mean reversion for winner and loser portfolios formed based on prior returns of 12 months or less. However, test results show evidence of significant mean reversion for the winner and loser portfolios constructed based on their prior 24 months and 36 months returns. In addition, the study reveals that the mean reversion is more significant for longer-formation-period portfolios as well as for longer holding periods. The examination of the cumulative loser-winner spreads obtained from the contrarian portfolios based on the constituents’ prior 24 month and 36 month returns indicates that the contrarian returns increase for portfolios formed between 2004 and 2006, and declines thereafter towards the end of the examination period. The deterioration of contrarian returns coincides with the subprime mortgage crisis in 2007 and the subsequent global financial crisis in 2008. This evidence suggests that the degree of mean reversion on the JSE is positively correlated to the South African business cycle.

We examine the short-term price reaction of 424 UK stocks to large one-day price changes. Using the GJR-GARCH(1,1), we find no statistical difference amongst the cumulative abnormal returns (CARs) of the Single Index, the Fama–French and the Carhart–Fama–French models. Shocks ⩾5% are followed by a significant one-day CAR of 1% for all the models. Whilst shocks ⩽−5% are followed by a significant one-day CAR of −0.43% for the Single Index, the CARs are around −0.34% for the other two models. Positive shocks of all sizes and negative shocks ⩽−5% are followed by return continuations, whilst the market is efficient following larger negative shocks. The price reaction to shocks is unaffected when we estimate the CARs using the conditional covariances of the pricing variables.

Yes / Although a cornerstone of traditional finance theory, empirical evidence in support of a positive mean-variance relation is far from conclusive, with the behavior of retail investors commonly thought to be one of the root causes of departures from this expected relationship. The behavior of institutional investors, conventionally thought to be sophisticated and rational, has recently come under closer scrutiny, including in relation to investor sentiment. Drawing together these two strands of literature, this paper examines the impact of institutional investor sentiment on the mean-variance relation in six regions, including Asia (excl. Japan), Eastern Europe, Eurozone, Japan, Latin America, and the US, and across thirtyeight markets. Empirical evidence supports the differential impact of institutional investor sentiment on the mean-variance relation (i.e., positive or negative), both across regions and across markets. In particular, for markets with cultural proneness to overreaction and a low level of market integrity institutional investor sentiment tends to distort the risk-return tradeoff.

This dissertation consists of two essays. In the first essay, I examine the source of momentum in stock returns. The reversal of momentum returns has been interpreted as evidence that momentum results from delayed overreaction to information. I examine momentum and reversals conditional on firms’ share issuance (net of repurchases) during the momentum holding period and show that (1) among losers, the momentum returns are statistically significant, but the reversals are non-existent, for both issuers and non-issuers; (2) among winners, momentum and reversals are restricted to issuers, but are non-existent among non-issuers. After further conditioning on firm size, I find that winner reversals are restricted to small, equity issuing firms. After excluding these small issuers from the sample, the remaining firms have strong momentum profits with no accompanying reversals. The evidence suggests that the return reversals are a manifestation of the poor performance of equity issuing firms. Further, while investor overreaction potentially contributes to the momentum among winners, a large fraction of firms do not earn any significant abnormal returns following initial price continuation, suggesting that underreaction, and not delayed overreaction to information, is the dominant source of momentum in stock returns. In the second essay, I examine alternative explanations of reversals in stock returns. George and Hwang (2007) find that long-term reversals in stock returns are driven by investors’ incentive to defer payment of taxes on locked-in capital gains rather than by overreaction to information. I show that return reversals are instead attributable to the negative relationship between firms’ composite share issuance and future stock returns documented in Daniel and Titman (2006). The ability of locked-in capital gains measures to forecast stock returns is largely subsumed by the composite share issuance measure. My results do not support the hypothesis that capital gains taxes drive long-term return reversals. / Ph. D.

新上市股的長期績效優於市場,但相較於五年未發行新股的對照公司則較差,而在市場空頭時期上市的股票績效卻相對較佳.和未發行新股的對照公司相較,股票的年報酬率變化呈現碗狀的趨勢,在上市後的營運績效有下滑的現象,隱含投資人有過度樂觀的情形.新股發行效果存在,即新上市股在上市五年內對預期報酬率都有負的影響.此效果和規模效果,市價淨值效果同時存在而無法取

本研究乃使用民國七十三年至八十三年股票報酬與公司財務資料進行實證分析。研究的目的在於探討使用年、月、週、日報酬資料時： 　　(1).臺灣股票市場是否存在過度反應現象。 　　(2).控制公司風險後，臺灣股票市場是否仍然存在過度反應現象。 　　(3).控制公司規模後，臺灣股票市場是否存在過度反應現象。 　　(4).同時控制公司風險與公司規模後，臺灣股票市場是否還存在過度反應現象。 　　研究結果發現，在未控制其他任何變數時，民國八十年至八十二年間有過度反應的現象。在控制公司風險時，實證的結果顯示民國八十年至八十三年間臺灣股市有過度反應的現象。當控制公司規模時，實證的結果顯示僅有民國八十年至八十二年間臺灣股市有過度反應的現象。當同時控制公司規模與公司風險，臺灣股市在民國七十九年以後均有過度反應的現象。

Magister Commercii - MCom / The primary objectives of this research are to determine whether indices constructed from fundamental attributes of ALSI constituents outperform indices weighted by market capitalisations; and whether the performance of fundamental indices could be explained by size and value risk factors. The examination period is 1st January 2000 to 31st December 2009. The JSE ALSI constituent’s fundamental attributes; book values, dividends, earnings and sales together with their market values are extracted from DataStream International. Indices are subsequently constructed according to share’s market values and the four aforementioned fundamental attributes as well as a composite metric. The composite metric is a combination of all four fundamental attributes. Fundamental indices are found to be more mean-variance efficient than cap-weighted indices, whilst displaying moderate value bias and minor size bias. Fundamental indices exhibit lower risk-adjusted returns when rebalanced less frequently, except for sales-weighted indices which justly capture undervalued shares that mean revert throughout the year. Fundamental indexation is therefore, adjudged to be superior to cap-weighted methods and only relatively affected by value effect

The present thesis is focused on speculative behavior of investors in financial markets. More precisely, the thesis consists of five papers and takes a closer look at two speculation driven financial market anomalies, the overreaction hypothesis and the momentum effect, and considers them in two financial markets, cryptocurrency and commodity markets.

I denna uppsats kommer vi att undersöka om det förekom överreaktioner på Stockholmsbörsen mellan åren 2002 och 2016. Överreaktioner undersöks genom att bilda vinnar- och förlorarportföljer baserat på tidigare månatliga avvikelseavkastningar. Vi ställer en hypotes om att förlorarportföljer kommer att prestera bättre än vinnarportföljer efter portföljformering. Portföljerna utvärderas under ett-, två- och treårsperioder för att undersöka om det förekommer reversals som en investerare skulle kunna utnyttja genom contrarianstrategin. Vår uppsats identifierar kortsiktiga reversals direkt efter portföljformering, men på lång sikt tenderar investerare att erhålla vinst genom att följa en positiv marknadstrenden. Regressionsanalyser med CAPM och Fama-French trefaktormodell genomförs för att få en bättre förståelse av orsakerna som ligger bakom avkastningar i vinnar- och förlorarportföljer. Vi föreslår att reversals inte skapar möjligheter för investerare att nå positivt statistiskt signifikant alfa på Stockholmsbörsen. Möjliga vinster genom contrarianstrategin drivs av faktorer som företagsstorlek och –värde snarare än att investerare överreagerar på marknaden. / In this study we will examine if overreactions occurred on the Stockholm Stock Exchange during period 2002-2016. Winner- and loser portfolios were formed based on past monthly returns to see if investors overreact and by doing that cause reversal effects later on. Our study discovers short-term reversals, but in the long run investors benefit by following the overall trend on the stock market. Expanding our study to the Fama-French three-factor model we suggest that reversals in stock prices does not enable investors to gain statistically significant positive alphas on the Stockholm Stock Exchange. On the contrary, returns are driven by the factors of firm size and -value rather than behavioral biases of investors.